Three layers of working memory: Focus-switch costs and retrieval dynamics as revealed by theN-count task

Abstract

Two experiments explored the process of switching items in and out of the focus of attention using a new paradigm, the N count task (adapted from Garavan, 1998; N varied from 1 to 4). This task yielded a focus size of one, indicated by a substantial focus switch cost for 2 count. Additionally, the focus switch costs in response time increased with working memory load, indicating an effortful search process occurring at a speed of about 240 ms/item. Maintaining and switching to and from a passive load did not increase the focus switch costs or decrease memory accuracy, indicating that there is no crosstalk between passive and active items. The results support a concentric theory of working memory: a small focus at its core, a surrounding area of (at least) three readily available items referred to as the outer store, and a still wider region of passive storage, possibly more long term memory than working memory.

Working memory updating involves item-specific removal

“…On the one hand, this demonstrates that removal is an item-specific process, and thus supports the assumption, derived from SOB, that removal operates via unlearning of a specific item-context association. On the other hand, this finding supports the notion that people try to avoid the costs associated with switching their focus of attention (Basak & Verhaeghen, 2011;Oberauer, 2002) and also their operational mode of WM (see below and Kessler & Oberauer, in press). A precedent for the avoidance of switch costs can be found in the literature on problem solving and categorization, where people may continue to use a suboptimal strategy to avoid strategy switch costs (Kalish et al, 2005;Lemaire & Lecacheur, 2010;.…”

Effects of Education on Executive Functioning and its Trainability

“…In the outer store, representations are subject to interference and decay (Verhaeghen & Basak, 2005). Whenever an item representation stored outside the focus of attention is needed for some subsequent operation, the required element must be retrieved into the focus of attention at the expense of the item already residing there (Basak & Verhaeghen, 2011). This shunting process of swapping item representations into and out of the focus of attention is called focus-switching (Voigt & Hagendorf, 2002).…”

Attentional refreshing of information in working memory: Increased immediate accessibility of just-refreshed representations

“…The item that is represented in the focus of attention is assumed to be in a privileged state of heightened accessibility (e.g., Basak & Verhaeghen, 2011;Cowan, 1995;McElree, 2006;Nee & Jonides, 2008;Oberauer & Refreshing in WM 7 Hein, 2012). The presumed local effect of refreshing on WM representations is thus the heightened accessibility of the just-refreshed WM representation.…”